JPH10323902A - Vibration-welded molding made of polyamide resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve strength, heat resistance, chemical resistance and welding strength by welding by vibrating a plurality of moldings made up of a chemical compound containing some number of pieces falling within a range of specific values of a carboxyl group and some parts by weight falling within a range of specific values of glass fiber for specific pts.wt. of polyamide resin. SOLUTION: 10-50 pts.wt. of glass fiber and 0.005-10 pts.wt. of chemical compound containing 2-4 pieces of a carboxyl group are blended with 100 pts.wt. of polyamide resin. When the amount of the blended glass fiber is not more than 10 pts.wt., the welding straight of the polyamide resin decreases, and when the amount exceeds 150 pts.wt., the fluidity diminishes. The glass fiber is preferably of such a type this is normally used for a thermoplastic resin, and especially, more preferably of the chopped strand type based on non-alkali fiber glass. The chemical compound containing 2-4 pieces of a carboxy group to be used is preferably, a chemical compound containing 2 or 3 pieces of the carboxyl group such as azipinic acid, terephthalic acid or 1,2,4- benzenetricarboxylic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration-welded molded article made of a polyamide resin, and more particularly to a vibration-welded molded article of a polyamide resin obtained by joining a plurality of primary molded articles by vibration welding. Things.

[0002]

2. Description of the Related Art In recent years, applications of plastics have been expanded,
Taking advantage of this property, various industrial products, such as intake manifolds for automobile engines, have been converted into resins by the vibration welding method. As a material for resinification, glass fiber reinforced 66 nylon or glass fiber reinforced 6 nylon is used.

However, in the conventional method, even if the primary molded article is welded by the vibration welding method, a satisfactory welding strength cannot be obtained. For example, an automobile engine in which the vibration weld molded article is a hollow body molded article In the case of the intake manifold described above, sufficient pressure resistance cannot be obtained, and the intake manifold may be damaged when the internal pressure increases due to backfire of the engine or the like. For this reason, as a means for improving the welding strength, a method of increasing the relative viscosity of the polyamide resin to be used, a method of increasing the welding area, and the like are known, but in the former, a decrease in fluidity occurs, and in the latter, A design change was required.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a vibration-welded molded article made of a polyamide resin which is excellent in strength, heat resistance, chemical resistance and welding strength.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its gist is as follows.
Polyamide resin obtained by blending (B) 10 to 150 parts by weight of glass fiber and (C) 0.005 to 10 parts by weight of a compound containing 2 to 4 carboxyl groups with respect to 100 parts by weight of (A) polyamide resin. The present invention relates to a vibration-welded molded product made of a polyamide resin obtained by vibration-welding a plurality of molded products which are primarily molded using the composition.

Hereinafter, the present invention will be described in detail. As the polyamide resin (A) in the present invention, polymerizable ω-amino acids or lactams thereof, preferably 3
A polyamide resin obtained by using a lactam having at least a member ring or a dibasic acid and a diamine as a raw material and performing polycondensation thereof is exemplified. As ω-amino acids, ε-
Examples include aminocaproic acid, 7-aminoheptanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Lactams include ε-caprolactam, enantholactam, caprylactam, lauryl lactam, α-pyrrolidone and α-piperidone.

The dibasic acids include adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dimer acid, undecandionic acid, dodecadionic acid, hexadecadionic acid, hexadecenedionic acid, eicosandioic acid , Eicosadienedioic acid, diglycolic acid, 2,2,4-trimethyladipic acid, xylylenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid,
Terephthalic acid and isophthalic acid;

The diamines include hexamethylenediamine, tetramethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4 (or 2,4,4) -trimethylhexamethylenediamine, bis-methylenediamine, and bis-methylenediamine. (4,4'-aminocyclohexyl) methane and meta-xylylenediamine.

As the polyamide resin in the present invention,
Preferably, 6 nylon, 66 nylon, 66/6 copolymer nylon or the like is used, and more preferably, 6 nylon is used. Further, a plurality of the above-mentioned polyamide resins may be used.

The relative viscosity of the polyamide resin in the present invention is preferably from 2.0 to 4.0. Here, the relative viscosity is a value measured at a concentration of 1% in 98% sulfuric acid and a temperature of 25 ° C. according to JIS K6810. If the relative viscosity is too low, the welding strength will be low, and if it is too high, the fluidity will decrease. The relative viscosity of the polyamide resin is more preferably from 2.5 to 3.7.

The glass fibers used in the present invention may be those usually used for thermoplastic resins, and preferably include chopped strands made of E glass (non-alkali glass). Fiber diameter of glass fiber is 1
To 20 μm, preferably 5 to 15 μm. As the glass fiber, a glass fiber that has been surface-treated with a silane coupling agent or the like to improve the adhesion to the polyamide resin is preferable.

The compounding amount of the glass fiber is 10 to 150 parts by weight based on 100 parts by weight of the polyamide resin (A). If the amount of the glass fiber is less than 10 parts by weight, the welding strength decreases, and if it exceeds 150 parts by weight, the fluidity decreases. The blending amount of glass fiber is (A) polyamide resin 10
It is preferably 15 to 120 parts by weight, more preferably 20 to 100 parts by weight, based on 0 parts by weight.

The compound (C) having 2 to 4 amino groups in the present invention is preferably a compound represented by the following general formula (1).

[0014]

Embedded image R- (COOH) _n (1)

(Wherein, R represents a divalent to tetravalent aliphatic hydrocarbon group, a divalent to tetravalent alicyclic hydrocarbon group, or a divalent to tetravalent aromatic hydrocarbon group; 2, 3, or 4.)

Specific examples of the compound having 2 to 4 carboxyl groups in the present invention include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid,
Suberic acid, azelaic acid, sebacic acid, dimer acid,
2,2,4-trimethyladipic acid, xylylenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, maleic acid, fumaric acid, tricarballylic acid, 1,2,4-benzenetricarboxylic acid Acids, 1,3,5-benzenetricarboxylic acid, ethanetricarboxylic acid, benzenetetracarboxylic acid, silicone oil containing 2 to 4 carboxyl groups, and the like,
Preferably, adipic acid, terephthalic acid, 1,2,4-
Compounds containing two or three carboxyl groups such as benzenetricarboxylic acid are exemplified.

The compounding amount of the compound containing 2 to 4 carboxyl groups is 0.1 to 100 parts by weight of the polyamide resin.
005 to 10 parts by weight. If the amount is less than 0.005, the welding strength is insufficient, and if it exceeds 10 parts by weight, mold contamination during injection molding becomes significant. The compounding amount of the compound containing 2 to 4 carboxyl groups is as follows.
It is preferably 0.01 to 5 parts by weight, more preferably 0.03 to 3 parts by weight, based on 00 parts by weight.

In the polyamide resin composition of the present invention, inorganic fillers other than glass fibers, such as glass flakes, glass beads, mica, talc, kaolin, wollastonite, and the like, as long as the effects of the present invention are not impaired.
A potassium titanate whisker or the like may be blended. Further, known additives such as a heat stabilizer such as a copper compound, a releasing agent, and a coloring agent such as carbon black may be blended. These blending is carried out at any stage from the polymerization of the resin to the molding, but it is preferable to carry out melt-kneading using an extruder.

In the vibration-welded molded product made of a polyamide resin of the present invention, first, a plurality of parts are first molded respectively using a polyamide resin composition. As a molding method of a molded article obtained by primary molding, a molding method generally used in molding of a thermoplastic resin is applied, and preferably, an injection molding method is used. The plurality of molded products obtained by the primary molding in the present invention may have the same shape or different shapes from each other, for example, a molded product having a shape as shown in FIG. 1 or a hollow body as shown in FIG. A molded product having a shape shown in FIG. 3 in which a three-way tube is cut in a longitudinal direction is exemplified.

Next, a plurality of primary molded products are joined by vibration welding to obtain a polyamide resin vibration welded molded product. The frequency of vibration in vibration welding is 100 to 3
00 Hz, and the amplitude is 0.5 to 2.0 mm, preferably 0.8 to 1.6 mm. The welding pressure is 5
100 kg / cm ² , preferably 10 to 60 kg
/ Cm ² . If the welding pressure is too high or too low, the welding strength will decrease. The welding time, which should be under a predetermined pressure, is set so that the desired melting allowance is obtained,
The holding time after releasing the pressure is set so that the welded portion is sufficiently solidified.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention.

The raw materials used in the present invention are as follows. (1) Polyamide resin: 6 nylon, manufactured by Mitsubishi Engineering-Plastics Corporation, NOVAMID 10
15J (relative viscosity 3.0). (2) Glass fiber: Nippon Electric Glass Co., Ltd., trade name T
249GH. (3) Compound containing 2 to 4 carboxyl groups: terephthalic acid, manufactured by Wako Pure Chemical Industries, Ltd. (4) Compound containing three carboxyl groups: 1, 2,
4-benzenetricarboxylic acid, manufactured by Wako Pure Chemical Industries, Ltd.

The method for evaluating the vibration welding strength is as follows. (5) Test piece for measuring welding strength: Injection molding is performed under the conditions described in Examples described later to obtain two primary molded articles having the same shape shown in FIG. Subsequently, vibration welding was performed under the conditions described in Examples described later to obtain a vibration welded molded product shown in FIG. (6) Measuring method of welding strength: This vibration-welded molded product is manufactured by Orientec Co., Ltd. using Tensilon UTM-III-50.
Using a 0-type testing machine, tension was applied under the conditions of a tensile speed of 5 mm / min and a distance between chucks of 80 mm, and the breaking strength at the welded portion was defined as the weld strength.

Example 1 At the compounding ratio shown in Table 1,
Terephthalic acid and glass fiber were blended with the polyamide resin. The composition is TEM-35 manufactured by Toshiba Machine Co., Ltd.
The set temperature was 280 ° C. using a B-type twin-screw kneader. Using the obtained glass fiber reinforced polyamide resin composition, IS manufactured by Toshiba Machine Plastic Engineering Co., Ltd.
Set temperature 260 by 80EPN-2A type injection molding machine
At 80 ° C. and a set mold temperature of 80 ° C., two primary molded articles having the same shape as shown in FIG. 1 were obtained.

Next, a pair of the primary molded products was used as a VIBRATION WELDER manufactured by Emerson Japan.
Using a Model 2800 vibration welding machine, the frequency was 240 Hz, the welding pressure was 15.5 kg / cm ² , and the amplitude was 1.
5 mm, melting margin 1.5 mm, Hold pressure: pressure 15.5 kg / cm ² after stopping vibration, holding time 5.0 sec
To obtain a vibration welded molded product shown in FIG. CX made by Emerson Japan, Inc. to control the melting allowance
A 132 type non-contact WDC welding size control device was used. Table 1 shows the measurement results of the welding strength of the obtained vibration welding molded product.

Examples 2 and 3 1,2,4-benzenetricarboxylic acid and glass fiber were mixed with a polyamide resin in the mixing ratio shown in Table 1. For the compounding, a TEM-35B type twin screw kneader manufactured by Toshiba Machine Co., Ltd. was used, and the set temperature was 280 ° C. Using the obtained glass fiber reinforced polyamide resin composition, a primary molded product and a vibration weld molded product were obtained in the same manner as in Example 1. Table 1 shows the measurement results of the welding strength of the obtained vibration welding molded product.

Comparative Example 1 At the compounding ratio shown in Table 1,
Glass fiber was blended with the polyamide resin. In the formulation,
The set temperature was 280 ° C. using a TEM-35B twin screw kneader manufactured by Toshiba Machine Co., Ltd. Using the obtained glass fiber reinforced polyamide resin composition, a primary molded product and a vibration weld molded product were obtained in the same manner as in Example 1. Table 1 shows the measurement results of the welding strength of the obtained vibration welding molded product.

Comparative Example 2 At the compounding ratio shown in Table 1,
Terephthalic acid and glass fiber were blended with the polyamide resin. The composition is TEM-35 manufactured by Toshiba Machine Co., Ltd.
The set temperature was 280 ° C. using a B-type twin-screw kneader. Using the obtained glass fiber reinforced polyamide resin composition, a primary molded product and a vibration weld molded product were obtained in the same manner as in Example 1. Table 1 shows the measurement results of the welding strength of the obtained vibration welding molded product.

[0028]

[Table 1]

[0029]

Industrial Applicability The vibration-welded molded article made of a polyamide resin of the present invention has excellent strength, heat resistance, chemical resistance, and remarkably excellent welding strength, and is effective for molded articles in various fields. It is effective for intake manifolds for automobiles that require high safety.

[Brief description of the drawings]

FIG. 1 shows the shape of a primary molded product (60 mm × 25 mm × 4 m
Explanatory diagram showing an example of m)

FIG. 2 is an explanatory view showing an example of the shape of a vibration welding molded product.

FIGS. 3A and 3B are plan views showing examples of shapes of a pair of hollow body molded products.

FIG. 4 is a conceptual diagram showing an example of a vibration-welded hollow body molded product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Welding surface 2, 2 'Upper opening 3 Lower opening

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI // B29K 77:00 B29L 22:00 23:00 (72) Inventor Tatsuya 5-5-2 Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Mitsubishi Engineering Plastics Corporation Technology Center

Claims (4)

[Claims] 1. A compound (B) containing 10 to 150 parts by weight of glass fiber and (C) a compound containing 2 to 4 carboxyl groups per 100 parts by weight of a polyamide resin.
A vibration-welded molded article made of a polyamide resin obtained by vibration-welding a plurality of molded articles that are primarily molded using a polyamide resin composition containing from 0.05 to 10 parts by weight. 2. The polyamide resin vibration welding molding according to claim 1, wherein the compound (C) containing 2 to 4 carboxyl groups is a compound represented by the following general formula (1). Goods. ## STR1 ## _{R- (COOH) n (1)} ( wherein, R, 2-4 divalent aliphatic hydrocarbon group, a divalent to tetravalent alicyclic hydrocarbon group or a divalent to tetravalent aromatic, A group hydrocarbon group, and n is 2, 3 or 4.) 3. The vibration welded product made of polyamide resin according to claim 1, wherein the polyamide resin is 6 nylon, 66 nylon or 6/66 nylon. 4. The vibration-welded molded article made of a polyamide resin according to any one of claims 1 to 3, wherein the vibration-welded molded article made of a polyamide resin is a hollow molded article.